Rotary jar



Jan.l7,1939.. f J.H.IBYISHOP T ,1 ,1

' ROTARY JAR Original Filed July so, 1929 INVENTOR Jorm H.B1snar. B

\ ATTORNEY Patented Jan. 17, 1939 UNITED STATES ROTARY JAR John H. Bishop, Los Angeles, C'alif., assignor of sixteen and two-thirds per cent to Jack Donovan, Whittier, Calif.

Substitute for abandoned application Serial No.

382,178, July 30, 1929. This application February 11, 1936, Serial 2 Claims.

This is a renewed application filed in place of my forfeited application, Ser. No. 382,178, filed July 30, 1929.

This invention relates to a rotary jar, by means of which a tool which has become fastened in the hole may be jarred loose by the usual rotating movement of the drill pipe.

An object of my invention is to provide a rotary jar which can be used during the drilling of the well, and which can be brought into operation to jar the tool by pulling upwardly on the drill pipe, and then rotating the drill pipe in the usual clockwise direction.

A further object is to provide a rotary jar of the character stated which will in no way interfere with the usual rotary drilling of a well.

Other objects, advantages and features of invention may appear from the accompanying drawing, the subjoined detailed description, and the appended claims.

In the drawing:

Figure 1 is a longitudinal sectional view of my Jar.

Figure 2 is a sectional View taken on line 22 of Figure 1.

Figure 3 is a fragmentary side elevation of the jarring stem, the head thereon being shown in section.

Figure 4 is a fragmentary longitudinal sectional view of the lower part of the body.

Referring more particularly to the drawing, the numeral l indicates the cylindrical body of the tool which is provided with threads upon the upper end thereof as at 2, whereby the tool is secured to the drill pipe or the like. A jarring stem 3 is adapted to extend into the cylindrical and tubular body I and the stem is provided with a box or pin 4 on the lower end thereof to which the tool. such as a bit is secured. A heavy multisided nut 5 is formed immediately above the box 4 and is preferably integral with the stem and box.

The body I is formed with a multi-sided recess 6 in the bottom thereof which fits over the nut 5 for the purpose of rotating the tool as will be further described. The stem 3 is provided with a head i on the top thereof, said head being preferably screwed onto the top of the stem as shown in Fig. 3. The head I is locked in position on the stem in any suitable manner, for example, by means of a nut B which is hexagonal on the outside, and which fits over the square 9 on the top of the stem. The hexagonal part of the nut fits into an appropriate recess in the head and a cotter key Ill extends thru the stem 3 above the nut.

The head I is provided with a slightly enlarged ring II on the top thereof, and the body is provided with a shoulder 12 which is adapted to engage the ring I I when the tool is removed from the well. The head I is formed with a plurality I of cam surfaces I 3 on the bottom thereof, said surfaces being adapted to cooperate with cam surfaces i l on the top of a slidable sleeve M on the stem 3. The sleeve I5 is caused to rotate with the body I by means of a plurality of pins G6 which extend into key ways ll in the sleeve.

A coil spring l8 surrounds the stem 3 and bears against the bottom of the sleeve l5 and against a ring it which rests upon shoulders 20 in the body I. During the drilling operations of the well, when the bit is progressing into the formation, there is considerable weight upon the bit from the drill pip-e above, and this weight holds the body l in position around the nut 5 as shown in Figure l. The spring I8 is not long enough to hold the sleeve it against the head i during the normal drilling operation. If the bit becomes stuck in the hole, the drill pipe is pulled upwardly in order to release the body I from the nut 5 and this action also compresses the spring i8, which in turn, forces the sleeve l5 against the head 5. Continued rotation of the .drill pipe in a clockwise direction will drive the sleeve, and the head i will be stationary because the stem 3 is secured to the bit. The relative rotation of the members 7-45 will cause the cam surfaces iii-4'3 to slide over each other and thus create a bump or jar upwardly against the stem 3. This continued bumping or jarring will eventually release the bit so that the drilling operations can be continued. In continuing to drill, it is only necessary to again permit the weight of the drill pipe to be exerted upon the bit and the recess 6 of the body i will fit over the nut 5, and the bit will be rotated in the usual manner.

Having described my invention, I claim:

1. A rotary jar comprising a body adapted to be secured to drill pipe or the like, a stem adapted to extend into the body, tool coupling means on the stem, a multi-sided driving nut on the stem, said body having a recess adapted to fit over the nut, a head on the stem, a sleeve rotatably mounted on the stem, driving pins extending from the body into the sleeve, said head and sleeve being provided with co-acting cam surfaces, and spring means yieldably urging said cam surfaces together.

2. A rotary jar comprising a body adapted to be secured to drill pipe or the like, a stem adapted to extend into ,the body, tool coupling means on the stem, a multi-sided driving nut on the stem, said body having a recess adapted to fit over the nut, a head on the stem, a sleeve rotatably mounted on the stem, driving pins extending from the body into the sleeve, said head and sleeve being provided with co-acting cam surfaces, and a coil spring surrounding the stem and adapted to bear against the sleeve to yieldably urge the same against the head.

JOHN H. BISHOP. 

